1. Field of the Invention
The present invention relates to improvements of a tape cassette loading system equipped in a magnetic recording and/or reproducing apparatus, for loading a tape cassette accommodating a magnetic tape wound around a pair of tape reels, and it particularly relates to a tape cassette loading system having a tape slack take-up mechanism capable of taking-up a tape slack of the magnetic tape occurring in the tape cassette by rotating at least one of the tape reels within the tape cassette, when the tape cassette is loaded in the cassette loading system equipped in the apparatus.
2. Description of the Related Art
Presently, such a magnetic recording and/or reproducing apparatus as having rotary magnetic heads, for instance, a Video Tape Recorder (VTR) or a Rotary head Digital Audio Tape recorder (R-DAT) is widely used together with a magnetic tape cassette (referred to as a "tape cassette" or a "cassette" hereafter) accommodating a magnetic tape wound around a pair of tape reels.
Upon a recording or a reproducing operation, the tape cassette is first loaded in a cassette loading device of the apparatus, then is automatically transferred to a predetermined set position by a transferring operation of the cassette loading device by a cassette transfer mechanism, while a front lid of the tape cassette is rotated upward to open by a lid opening mechanism. A segment of the magnetic tape being between the pair of tape reels is positioned just behind the front lid with its closed position. Thus, upon the tape loading, a pair of loading poles enters into a mouth provided at a bottom of the cassette to intercept and engage with the tape segment to draw it out of the cassette with its lid being open, subsequently, the loading poles move respectively to predetermined positions so as to bring the magnetic tape obliquely around a rotary head drum in a predetermined range. Then, recording or reproducing of signals on or from the magnetic tape is performed by rotary magnetic heads fixed to the rotary head drum.
When a user manually rotates a tape reel or reels for some reason before loading the cassette into a recorder or when the cassette 100 is shaken violently, the tape segment just behind the front lid is liable to be slackened and often a tape slack within the cassette as illustrated in FIG. 1 develops. FIG. 1 is a plan view showing a tape cassette in which a magnetic tape has a tape slack. Referring to FIG. 1, a magnetic tape 101 is accommodated in the cassette 100 in such a manner that both ends of the magnetic tape 101 are respectively wound around and anchorred to a pair of tape reels, a supply reel 102 and a take-up reel 103. The tape segment 101a between the tape reels 102, 103 contacts guide rollers 104, 106 disposed behind a lid 105 which can be rotated upwards to open.
Usually, a tape reel brake mechanism (not shown) utilizing friction or the like is used in the cassette 100 to prevent the tape segment 101a from unintended rotation of the reels and developing tape slacks in order not to disturb the insertion of the loading poles upon the tape loading.
However, when at least one of the tape reels 102, 103 is rotated in a tape slacking direction by an erroneous handling against the friction provided by the tape reel brake mechanism, a tape slack develops at the tape segment 101a. It should be noted that the tape slack often poses problems to the recorder, and/or the tape not only disturbing the engagement of the loading poles with the tape segment 101a, but also may cause the serious problem of the tape being jammed inside the recorder causing a tape or recorder damage or both.